NODULARIA 987 
Unio mornatus Lea, Pr. Ac. N. Sci. Phila., VIII, 1856, p.-93; 
Obs:, VI, 1857, p13; pl. xxiv, fig. 6; Jl. Ac: N. Sci. Phila., 
PE aie ep: 2024 ply KTV ei k6: 
Margaron (Unio) tmornatus Lea, Syn., 1870, p. 47. 
Nodularia inornata Simpson, Syn., 1900, p. 813. 
Physunio imornatus Haas, Conch. Cab., Unio, 1912, pl. 34 
figs. 3-4. 
Much thinner than cerulea, to which it seems closely related, 
and not so pointed nor angulated behind. ‘The beak sculpture 
appears to be zigzag radial, but the beaks are too badly 
eroded in all the specimens seen to allow: of any definite con- 
clusion. 
> 
NopulLARIA PACHYSOMA (Benson). 
Shell somewhat elongated, inflated, rather solid, inequilat- 
eral; beaks full and high, their sculpture zigzag radial, not ex- 
tending over the disk; posterior ridge strong, apparently in- 
clined to be double, curved down in the middle, ending behind 
in a blunt point on the median line; anterior end rounded, 
subangulate above; base line lightly curved, quite full behind 
the middle; dorsal slope decidedly and obliquely truncate; 
surface apparently nearly smooth; epidermis bright green with 
faint, yellowish bands, with two or more dark green, posterior 
rays; hinge line nearly straight; teeth somewhat strong; lat- 
erals straight ; nacre pinkish. 
Length 45, height 22, diam. 20 mm. 
Assam. 
Unio pachysoma Brnson, Ann. and Mag., X, 1862, p. 186.— 
Haniey and THEOBALD, Conch. Ind., 1876, p. 6, pl. x1, 
Moir: 
Margaron (Unio) pachysoma Lea, Syn., 1870, p. 63. 
Nodularia pachysoma Simpson, Syn., 1900, p. 813. 
Unio pachystema Payret, Conch. Sam., III, 1890, p. 162. 
This species is smoother and much more inflated than 
cerulea, to which it is evidently nearly related, and it seems 
to be solider and brighter. The above description is drawn 
from the figures of this species in the Conchologia Indica, 
these figures being made from the type. 
